Deal: Rentals start at $1,778 for trips of five or more days for selected houseboats, from the 46-foot Expedition that sleeps six to a 75-foot Excursion that sleeps 12. The price doesn't include fuel, taxes or surcharges. When booking online or over the phone, use the promotion code "FALL2010."

When: Book by Aug. 18 to reserve a houseboat at the discounted rate for trips from Sept. 1 to Dec. 22 .

Tested: TheLake Powell Resorts & Marinas websitegives you the history of the lake, best places to visit, what to expect weather-wise and maps under the "Discover" tab at the top of the home page. To find the deal, go to "Plan" and click on "Fall Houseboat Offer." From here you can choose which marina you want to leave from: Wahweap in Arizona or Bullfrog on the eastern side of the lake in Utah.

I found the special rate available Sept. 3 to 7 over Labor Day weekend for the 46-footExpeditionleaving from Wahweap Marina. The boat holds 12 people and sleeps six, and has a water slide, stateroom, flat-screen TV, full kitchen and more. The rental costs $1,778.90 plus $168.95 tax for a total of $1,947.85 - roughly 25% off the regular rate. Note that you also must put down a refundable damage deposit of $600 when you reserve. You may also call the marina to make a reservation.

Lake Cumberland is known as the "Houseboating Capital of the World," and it sees millions of houseboaters each year. In honor of this, Kentucky governor Matt Bevin recently dedicated a bridge on Lake Cumberland in Monticello to houseboating.